/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alipay.test.acts.utils;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;

/**
 * Annotation Utils 
 * 
 * @author yuanren.syr
 * @version $Id: AnnotationUtils.java, v 0.1 2015年8月17日 下午1:02:34 yuanren.syr Exp $
 */
public class AnnotationUtils {

    /**
     * Get Specific Methods by Annotations
     * 
     * @param clazz
     * @param annotationClass
     * @return
     */
    public static <T extends Annotation> List<Method> findMethods(Class<?> clazz,
                                                                  Class<T> annotationClass) {
        if (clazz == null || annotationClass == null) {
            throw new NullPointerException();
        }
        List<Method> result = new ArrayList<Method>();
        for (Method method : clazz.getMethods()) {
            if (method.getAnnotation(annotationClass) != null) {
                result.add(method);
            }
        }
        return result;
    }

    /**
     * Get Specific Fields by Annotations
     * 
     * @param clazz
     * @param annotationClass
     * @return
     */
    public static <T extends Annotation> List<Field> findFields(Class<?> clazz,
                                                                Class<T> annotationClass) {
        if (clazz == null || annotationClass == null) {
            throw new NullPointerException();
        }
        List<Field> result = new ArrayList<Field>();
        for (Field field : clazz.getDeclaredFields()) {
            if (field.getAnnotation(annotationClass) != null) {
                result.add(field);
            }
        }
        return result;
    }
}
